Fill in the blank: Pro-impeachment constituents in Congressmember Jerrold Nadler’s Eighth Congressional District have been raring for him to face a fight from Adam Sullivan in the Democratic primary in September. Sullivan planned to run specifically because Nadler has refused to bring articles of impeachment against President Bush and Vice President Cheney. Impeachment advocates have singled out Nadler, charging that as chairperson of the House Judicial Subcommittee on the Constitution, Civil Rights and Civil Liberties, he has “the clout” to kick off impeachment proceedings. But the congressmember, they charge, is “in lockstep” with Speaker Nancy Pelosi and other Democratic leaders who dismiss impeachment, feeling it’s too late in the process, that they don’t have the votes in the House and that it would backfire and hurt Barack Obama’s chances to become president. Meanwhile, the Nadler foes cry, Dennis Kucinich last month filed 35 articles of impeachment against Bush. Sullivan, an actor, lives on W. 50th St. in Nadler’s district, which includes the Upper West Side, Chelsea, Greenwich Village, Lower Manhattan and Brooklyn. He’s never run for political office before. Nadler, Sullivan declared, “has earned the right to be challenged.” Be that as it may, the issue, as far as Sullivan’s candidacy, appears to be moot. A source tipped us off on Tuesday that Sullivan only registered as a Democrat in New York in June, when the deadline for him to do so was in October. Oops! Sullivan had registered in New York in 1997 as “blank,” which allowed him to vote in general elections only, not primaries, which he did in 2001, 2002 and 2004 — though not in the intervening years, according to New York City Board of Elections records. His last place of registration before then was in 1996 in Orlando, Fl. Marcus Cederqvist, New York City B.O.E. executive director, said a “general objection” has already been filed by someone against Sullivan’s petitions and that the board will do its own review soon, so it’s not looking too good for him to run as a Democrat. “No, he’s a blank,” Cederqvist said, adding that under B.O.E. rules, “He will become a Democrat after the general election.” Al Ronzoni, a Sullivan campaign staffer, said his candidate did “make a good-faith effort” to play by the rules and only found out he had goofed up after filing his petition signatures this month. Ronzoni said that on Monday, Sullivan filed a “certificate of appropriateness” to ask the Democratic Party to accept his candidacy. But our source said that’s not what a certificate of appropriateness is used for. Though Nadler apparently won’t face a pro-impeachment candidate this year, many are still wondering just why the famously progressive congressmember hasn’t taken Bush and Cheney to task by triggering a call for their ouster. Barry Klein, a Nadler campaign spokesperson, said, “No one in Congress has done more work to uncover evidence of the Bush administration’s potentially impeachable offenses than Jerry Nadler — from his leading opposition on issues such as torture, the rollback of habeas corpus rights, extraordinary rendition and warrantless wiretapping to his forcing of John Yoo, Douglas Feith and David Addington to testify before Congress. Unfortunately, as Representative Nadler has explained in meetings with Mr. Sullivan and other impeachment proponents, it is eminently clear that there aren’t more than a handful of votes in the House or the Senate to impeach the president at this time — and a broadly defeated effort to impeach would undermine our collective efforts to hold the Bush administration accountable and restore the rule of law. We take it as a compliment that impeachment proponents think Congressman Nadler can single-handedly flip Congress on this issue. This is why Dennis Kucinich and every other leading impeachment advocate in Congress — Robert Wexler, Lynn Woolsey, Maxine Waters and Barbara Lee — as well as former Congresswoman Elizabeth Holtzman, author of a seminal book on the subject, are strongly supporting Congressman Nadler’s re-election.” As for why Nadler didn’t attend a March 9 impeachment forum at Judson Memorial Church, sponsored by Village Independent Democrats and Chelsea Reform Democratic Club, Klein said, “Despite misleading advertising, that event was scheduled without co-ordinating with Congressman Nadler’s schedule. Ultimately, a conflict prevented him from attending.”